A hydraulic circuit for supplying oil to a pulley oil chamber, a torque converter, and a lubrication system of a transmission by means of a main pump and a sub pump simultaneously driven by an engine, in which, when the hydraulic pressure of the torque converter or the lubrication system decreases due to an insufficient discharge flow rate of the main pump at a time of sudden acceleration or sudden deceleration of a vehicle, the destination to which oil discharged by the sub pump is supplied is switched in the order: pulley oil chamber, torque converter, and lubrication system is known from Patent Document 1 below.